How can i input 0.001 value in solidity?

Question

I want to list token on marketplace and price in form 0.0001 or 0.2 etc how can i do that ? solidity just unit. thanks a lot.

Answer 1

Hi Developer advocate from Chainstack here.

Basically solidity doesn't support float point calculation.

If you are talking about Eth, the basic value of Solidity is Wei. So 0.5 eth is equivalent to 500000000000000000 Wei.

If you are talking about an ERC-20 token, you need to leverage the decimals field. For example. If you set your decimal to be 2 and someone calls transfer("0x123123_add_in_hex",234), he/she is transferring 2.34 tokens.

Hope that helps.

Answer 2

You can use exponential notation to do this:

uint256 value = 0.001e18;

Just make sure to write e18, since 1 ETH = 10^18 wei.

Answer 3

The only unit of value that we have that can be used to store decimal are the wei and the gwei. But what's the wei ? It's the unit used for gas.

How can we get a random number and convert it to wei ?

answer :

there are 1 billion wei in one gwei.
there are 10^9 or 1,000,000,000 gwei in one ether.
therefore 1eth is 10^18 wei.
number_to_store = etherAmount * 10**18;